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Code
H022 / H032
Leakage inductance of the
motor L [mH]
H023 / H033
Magnetizing current of the
motor I o [A]
H024 / H034
Total inertia J [kgm
H050
Proportional gain under
PI control mode (K p )
H051
Integration gain under
PI control mode (K i )
H052
Proportional gain under
P control mode (K p )
F002
Acceleration time
F003
Deceleration time
A044
Control mode
A045
Output gain (Vgain )
A081
AVR function
b022
OL restriction level
b041~b044
Torque limit level
b083
Carrier frequency
* Second and 3rd functions ([H2**] & [H3**]) have the same meaning for 2nd and 3rd motors.
Refer to Table 3 for standard (default) motor parameter settings for SJ300 series inverter.
© 2002 Hitachi America, Ltd.
Function
L does not influence control much compared to other
parameters, however a suitable value is recommended to be set.
Influences mainly the
Ÿ
Ÿ
2
]
Influences mainly speed and torque response performance
This should be the total inertia ( J) on the motor shaft,
including the inertia of the rotor of the motor and the load. See
table 2 for information on how to tune in each case.
à See appendix A for calculation of the total inertia.
Fine tuning of proportional portion of speed response factor.
Ÿ
Ÿ
(% based on [H005])
Fine tuning of Ki portion of speed response factor.
Ÿ
Ÿ
(% based on [H005])
See Remarks for H050
(% based on [H005])
Acc and Dec time influence the response. Even if
optimized tuning parameter values are set, actual motor speed will
change according to the set ramp time.
If a quick response is required, the ramps should be set as fast as
possible. Or, use LAC (LAD cancellation) to make the ramp invalid.
Control mode should be set to 03 (SLV), 04 (0-SLV) or 05 (V2).
Output gain scales the duty cycle of PWM output, regardless of
the input voltage of the inverter.
Decreasing output gain can solve the problem of motor instability,
however the output torque will also decrease in this case.
AVR function attempts to maintain a stable output voltage by
changing the duty cycle of the PWM output in real-time. If the input
voltage changes or bus voltage changes due to regeneration, motor
sees constant voltage. That means the motor efficiency will be better.
In some cases, disabling the AVR function can resolve motor
instability problems.
AVR function attempts to always mainain constant output voltage.
During operation, DC bus voltage is always changing, which
means AVR function is always acting to change the duty cycle of
PWM output voltage. Since it is an active control function it may
lead sometimes motor instability (unstable energy transmission).
In such cases, setting AVR OFF can solve the problem.
Set OL level [b022] as high as possible, or else disable it
(set [b021] to "00 "), because a rather high motor current is
required in low frequency area in the case of vector control.
High torque cannot be achieved if OL restriction is preformed.
Set torque limit level as high as possible, or else disable it
( = assign TL to an intelligent input terminal and leave it OFF),
because high motor current is required in the low frequency area
in the case of vector control.
Maximum torque cannot be achieved if torque limit is triggered.
Decreasing carrier frequency can solve the problem of motor
instability.
This is because the effect of dead time will be reduced.
torque at low
Large I o à Bigger torque (Too big I o à Over magnetizing)
Small I o à Smaller torque
Large K p àQuick response (Too high K p can cause instability.)
Small K p à Slow but stable response
Large K i à Quick response (Too high K i can cause instability.)
Small K i à Slow but stable response
6
Remarks
speed.
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